U.S. patent application number 09/745099 was filed with the patent office on 2001-07-12 for insertion system for intraocular lens.
This patent application is currently assigned to CANNON STAAR CO., INC.. Invention is credited to Kikuchi, Toshikazu, Kobayashi, Kenichi, Nakajima, Toshiyuki.
Application Number | 20010007942 09/745099 |
Document ID | / |
Family ID | 17696187 |
Filed Date | 2001-07-12 |
United States Patent
Application |
20010007942 |
Kind Code |
A1 |
Kikuchi, Toshikazu ; et
al. |
July 12, 2001 |
Insertion system for intraocular lens
Abstract
An insertion system for an intraocular lens includes an
intraocular lens having a deformable optical portion; a holding
member for holding the lens at a standby position in a state in
which no stress acts on the optical portion of the lens; a
deforming member for deforming the lens to a reduced size; and an
insertion device having an insertion tube through which the
deformed lens is inserted into an eye, and a pusher mechanism for
pushing and inserting the lens into the eye. The holding member
includes a lens moving mechanism for moving the lens from the
standby position to an insertion position at which the pusher
mechanism can push and insert the lens into the eye.
Inventors: |
Kikuchi, Toshikazu; (Tokyo,
JP) ; Nakajima, Toshiyuki; (Matsudo-shi, JP) ;
Kobayashi, Kenichi; (Tokyo, JP) |
Correspondence
Address: |
Richard P. Berg
LADAS & PARRY
Suite # 2100
5670 Wilshire Boulevard
Los Angeles
CA
90036-5679
US
|
Assignee: |
CANNON STAAR CO., INC.
|
Family ID: |
17696187 |
Appl. No.: |
09/745099 |
Filed: |
December 20, 2000 |
Current U.S.
Class: |
606/107 |
Current CPC
Class: |
A61F 2/1678 20130101;
A61F 2/1672 20130101 |
Class at
Publication: |
606/107 |
International
Class: |
A61F 009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 6, 1999 |
JP |
H11-285795 |
Claims
What is claimed is:
1. An insertion system for an intraocular lens, comprising: an
intraocular lens having a deformable optical portion; holding means
for holding the lens at a standby position in a state in which no
stress acts on the optical portion of the lens; deforming means for
deforming the lens to a reduced size; and an insertion device
having an insertion tube through which the deformed lens is
inserted into an eye, and a pusher mechanism for pushing and
inserting the lens into the eye, wherein the holding means includes
a lens moving mechanism for moving the lens from the standby
position to an insertion position at which the pusher mechanism can
push and insert the lens into the eye.
2. An insertion system for an intraocular lens according to claim
1, wherein a portion of the deforming means is provided on the lens
moving mechanism.
3. An insertion system for an intraocular lens according to claim
1, wherein the intraocular lens is an intraocular lens having a
deformable optical portion and loop-shaped support portions each
forming a predetermined angle with respect to the optical portion,
and a support-portion holding mechanism for holding the support
portions at a predetermined angle is provided.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a system for inserting a
deformable intraocular lens into the eye. Examples of such a
deformable intraocular lens include a deformable intraocular lens
that is inserted into the eye in place of the natural lens when the
latter is physically extracted because of cataracts, and a vision
correction lens that is inserted into the eye for the sole purpose
of vision correction.
[0003] 2. Description of the Related Art
[0004] In general, during cataract surgery, an intraocular lens is
inserted into the eye, from which the natural lens has been removed
(lens-removed eye), such that the intraocular lens is located in
the original position previously occupied by the natural lens and
restores vision. Various studies on the material and shape of such
an intraocular lens have been carried out since Ridley performed
the first implantation of an artificial lens in 1949.
[0005] In recent years, in addition to studies on intraocular
lenses which are used for vision restoration after cataract
surgery, intense studies on intraocular lenses for refractivity
correction have been ongoing. Such an intraocular lens for
refractivity correction is inserted into the eye which still has a
natural lens (lens-carrying eye), for correction of nearsightedness
or farsightedness.
[0006] In relation to cataract surgery, a technique for crushing
the lens tissue by means of ultrasonic emulsification and
suctioning the crushed tissue away has been popularized. This
technique enables performance of lens removal surgery to excise an
opaque lens through a small incision. Along with progress in the
operational technique itself, intraocular lenses themselves have
recently been improved. Such an improved intraocular lens is
disclosed in, for example, Japanese Patent Application Laid-Open
(kokai) No. 58-146346. In the intraocular lens, the optical portion
is made of a deformable elastic material. The intraocular lens is
inserted, in a folded state, into the eye through a small incision
and restored to its original shape within the eye allowing it to
exert its proper lens function.
[0007] Accompanying these technical developments, the material of
the optical portion of such an intraocular lens has been changed
gradually from hard polymethyl methacrylate (PMMA) to silicone or
soft acrylic resin, which enables the intraocular lens to be
inserted into the eye in a folded state.
[0008] Moreover, in recent years, studies have been conducted on
copolymers such as hydroxyethyl methacrylate and methyl
methacrylate, as well as on hydrophilic materials such as
2-hydroxyethyl methacrylate (HEMA).
[0009] Further, intraocular lenses of different shapes have been
studied and put into practical use, including an intraocular lens
having a circular optical portion and loop-shaped support portions
formed of different materials, an intraocular lens whose
loop-shaped support portions and optical portion are formed of the
same material, and an intraocular lens having plate-shaped support
portions.
[0010] Furthermore, the following patent publications disclose
insertion devices for inserting the above-described deformable
intraocular lens into the eye in a compressed or folded state.
[0011] (1) Japanese Patent Application Laid-Open (kokai) No.
5-103803 discloses a device designed such that a holding member
which holds a folded lens is attached to a main body, and the lens
is inserted into the eye through an insertion tube provided at the
tip end of the holding member.
[0012] (2) Japanese Patent Application Laid-Open (kokai) No.
7-23991 discloses a disposable insertion device for one-time use in
which a portion for holding a folded lens is integrated with a main
body of the device and the entirety of the device is formed of
resin.
[0013] (3) Japanese Kohyo (PCT) Patent Publication No. 9-506285
discloses an intraocular-lens insertion device having a broadened
range of applications. In the intraocular-lens insertion device, a
lens is held in a stress-free state in an intermediate preparation
region of a main body. After attachment of a cannulae (insertion
tube) to the main body, the intraocular lens is inserted into the
eye through the cannulae. The intermediate region serves as a lens
package.
[0014] The conventional intraocular-lens insertion devices
described in (1) and (2) above have the following drawbacks. When
either of these devices is used, an intraocular lens removed from a
package is placed on a placement portion of the device, is
deformed, and then inserted into the eye. Therefore, during actual
operation, work for placing the intraocular lens onto the device is
needed, resulting in increased time and labor involved in
implantation of the intraocular lens.
[0015] Further, such an intraocular lens and insertion device must
be made germ-free through a sterilization procedure, because they
are inserted into the eye through an incision. However, if an
operator accidentally drops the lens and/or the insertion device
onto an unclean surface, such as a floor or table, during the
placement operation, the germ-free state is lost, and the lens
and/or the insertion device becomes unusable.
[0016] Further, when the operator forcedly inserts into the eye an
intraocular lens which has been placed on the device improperly,
the lens may be broken, or may forcibly fly out from the insertion
tube, potentially resulting in damage to the internal tissue of the
eye.
[0017] The intraocular-lens insertion device described in (3) above
has the following drawbacks. Although the intermediate region of
the device can be used as a lens package, work for attaching a
cannulae (insertion tube) to the main body must be performed during
actual use, because the cannulae (insertion tube) is a member which
is formed separately from the main body. Although a technique for
storing in advance an intraocular lens at the intermediate region
located on the center axis of a push rod, the intermediate region
is difficult to be formed from a material suitable for storing the
lens. In addition, the intermediate region cannot be formed to have
a function necessary for properly holding an intraocular lens
having loop-shaped support portions. That is, although such an
intraocular lens must be stored in a state in which the angle
between the optical portion and the support portions of the
intraocular lens is maintained, the intermediate region of the
conventional insertion device cannot provide such an angle
maintaining function.
SUMMARY OF THE INVENTION
[0018] An object of the present invention is to provide an
insertion system for a deformable intraocular lens, which can store
an intraocular lens in a state in which no stress acts on the
optical portion and the angle of the support portions is
maintained, to thereby eliminate the necessity of a
conventionally-used lens case having a mechanism for maintaining
the angle of the support portions of an intraocular lens.
[0019] Another object of the present invention is to provide an
insertion system for a deformable intraocular lens, which system
eliminates or simplifies an operation of placing a lens on an
insertion device to thereby save the time involved in the placement
operation, while solving drawbacks involved in conventional
insertion devices, such as breakage of a lens or improper insertion
of a lens, which would otherwise be caused by an improper operation
by an operator.
[0020] Still another object of the present invention is to provide
an insertion system for a deformable intraocular lens, which system
enables supply of an intraocular lens and an insertion device in a
sterilized sate.
[0021] In order to achieve the above objects, the present invention
provides an insertion system for an intraocular lens, comprising:
an intraocular lens having a deformable optical portion; holding
means for holding the lens at a standby position in a state in
which no stress acts on the optical portion of the lens; deforming
means for deforming the lens to a reduced size; and an insertion
device having an insertion tube through which the deformed lens is
inserted into an eye, and a pusher mechanism for pushing and
inserting the lens into the eye. The holding means includes a lens
moving mechanism for moving the lens from the standby position to
an insertion position at which the pusher mechanism can push and
insert the lens into the eye.
[0022] By virtue of the above-described configuration, an placement
operation for an intraocular lens can be completed by merely moving
the lens from the standby position to the insertion position by the
moving mechanism. This eliminates a conventionally practiced
operation of removing an intraocular lens from a lens case and
placing it on the insertion device. In addition, the insertion
system according to the present invention prevents erroneous
operation involved in the placement operation to thereby improve
safety.
[0023] Further, since the insertion system according to the present
invention is provided with a mechanism for holding an intraocular
lens at the standby position in a desired state, deformation of the
lens during storage can be prevented. Moreover, when packaging and
sterilization for the insertion device are performed in a sate in
which the lens is held in the insertion device, a completely
sterilized intraocular-lens insertion system can be provided.
[0024] Preferably, a portion of the deforming means is provided on
the lens moving mechanism. In this case, the function of the
intraocular-lens insertion system can be realized by a fewer number
of components.
[0025] Preferably, the intraocular lens is an intraocular lens
having a deformable optical portion and loop-shaped support
portions each forming a predetermined angle with respect to the
optical portion, and a support-portion holding mechanism for
holding the support portions at a predetermined angle is provided.
In this case, the function of preventing deformation of the lens
during storage to thereby maintain the original performance of the
lens can be achieved by a simple configuration.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Various other objects, features and many of the attendant
advantages of the present invention will be readily appreciated as
the same becomes better understood by reference to the following
detailed description of the preferred embodiment when considered in
connection with the accompanying drawings, in which:
[0027] FIGS. 1A and 1B are views showing an embodiment of the
intraocular-lens insertion system according to the present
invention, wherein
[0028] FIG. 1A is a front view of an insertion device showing a
state in which a lens holding member has been attached to the
insertion device and the intraocular lens is located at a first or
standby position, and
[0029] FIG. 1B is a front view of the insertion device showing a
state in which the lens is located at a second or insertion
position;
[0030] FIGS. 2A and 2B are enlarged views showing a portion of FIG.
1A, wherein
[0031] FIG. 2A is an enlarged front view showing a state in which
the lens holding member has been attached to the insertion device,
and
[0032] FIG. 2B is an enlarged plan view of the lens holding
member;
[0033] FIGS. 3A and 3B are cross sections of a main portion of the
embodiment shown in FIGS. 1A and 1B, wherein
[0034] FIG. 3A is an enlarged cross section taken along line 3A-3A
in FIG. 1A, and
[0035] FIG. 3B is an enlarged cross section taken along line 3B-3B
in FIG. 1B; and
[0036] FIG. 4 is a plan view showing a modified example of the
insertion tube of the insertion device of the embodiment of the
present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
[0037] FIGS. 1A and 1B show one embodiment of an intraocular-lens
insertion system according to the present invention. In the present
embodiment, an intraocular lens 20 horizontally stored in a lens
holding member 10 serving as holding means for the intraocular lens
20 can be moved between a first or standby position at which the
vertical position of the center of the intraocular lens 20 does not
coincide with the center axis of a push rod 33 of an insertion
device 30 and a second or insertion position at which the vertical
position of the center of the intraocular lens 20 coincides with
the center axis of the push rod 33 of the insertion device 30, so
that the intraocular lens 20 can be pushed out by the push rod 33.
Further, a push member 13 is provided as a lens moving mechanism
for moving the intraocular lens 20 from the first or standby
position to the second or insertion position.
[0038] FIG. 1A is a front view of the insertion device 30 to which
the lens holding member 10 has been attached to the insertion
device 30 and in which the intraocular lens 20 is located at the
first or standby position, and FIG. 2B is a front view of the
insertion device 30 in which the intraocular lens 20 is located at
the second or insertion position.
[0039] The system according to the present invention is mainly
composed of the lens holding member 10, which serves as lens
holding means for storing the intraocular lens 20, and the
insertion device 30 for inserting the intraocular lens 20 into the
eye of a patient.
[0040] The insertion device 30 includes a tubular main body 31, the
above-mentioned push rod 33, a pusher mechanism 34, and an
attachment portion 35. The tubular main body 31 of the insertion
device 30 is formed of transparent or semi-transparent plastic or
any other suitable material such that the diameter at the base end
31a is larger than that at the tip end 31b. The push rod 33 is
disposed to be located on the center axis of the tubular main body
31. The pusher mechanism 34 is disposed at the rear end 31a of the
tubular main body 31 of the insertion device 30 and is coupled to
the rear end of the push rod 33 so as to advance and retract the
push rod 33. The attachment portion 35 is formed at the tip end 31b
of the tubular main body 31 and adapted to receive the lens holding
member 10 serving as holding means. A tapered insertion tube 32 is
formed at the tip end of the attachment portion 35 such that the
through hole of the insertion tube 32 is aligned with the center
axis of the tubular main body 31. The intraocular lens 20 is pushed
out from the tip end 32a of the insertion tube 32 after being
deformed to a reduced size.
[0041] In the first or standby position shown in FIG. 1A, the
vertical position of the center of the lens does not coincide with
the center axis of the push rod 33 represented by an alternate long
and short dash line L. The intraocular lens 20 is stored within the
lens holding member 10 at the first or standby position shown in
FIG. 1A.
[0042] When a push member 13 of a top member 12 of the lens holding
member 10 is pushed downward in FIG. 1A, the intraocular lens 20 is
moved downward to the second or insertion position shown in FIG.
1B, at which the vertical position of the center of the lens
substantially coincides with the center axis of the push rod 33. In
this second or insertion position, the intraocular lens 20 can be
pushed out from the tip end 32a of the insertion tube 32 into the
eye through advance movement of the push rod 33 effected by the
pusher mechanism 34 provided at the rear end 31a of the tubular
main body 31.
[0043] FIGS. 2A and 2B are views showing an assembled state in
which the lens holding member 10 has been attached to the insertion
device 30, wherein FIG. 2A is an enlarged front view of the
insertion device 30, and FIG. 2B is an enlarged plan view of the
lens holding member 10.
[0044] The lens holding member 10 consists of the above-mentioned
top member 12 and a base member 11 having a structure suitable for
supporting the intraocular lens 20 having loop-shaped support
portions 22 made of a material different from that of the optical
portion 21. Specifically, the base member 11 has engagement
portions 11b which have inclined surfaces 11a of angle .theta.
extending in opposite longitudinal directions and maintaining the
angel .theta. between the optical portion 21 and the support
portions 22 of the intraocular lens 20. The nipping member 14 of
the top member 12 has on its bottom surface 14b inclined surfaces
14a to be mated with the inclined surfaces 11a of the base member
11. After placement of the lens 20 on the base member 11, the top
member 12 is placed on the base member 11, so that the support
portions 22 of the lens 20 are nipped between the base member 11
and the nipping member 14 of the top member 12.
[0045] As shown in FIGS. 2B, 3A, and 3B, the base member 11 of the
lens holding member 10 has an opening 11c in the top surface
thereof and projections 11e in the vicinity of the lower ends of
opposite side walls lid. The projections 11e elastically engage
with engagement steps 38 formed in the vicinity of the lower ends
of the lateral side surfaces of the attachment portion 35. The
longitudinal opposite ends of the base member 11 are opened so that
the base member 11 has a squarish C-like cross section. Further,
the paired engagement portions 11b are formed on the inner surfaces
of the side walls 11d to be located at the approximate center in
the vertical direction. The engagement portions 11b extend in the
longitudinal direction and adapted to receive the peripheral
portions of the optical portion 21 and the support portions 22 of
the intraocular lens 20. As shown in FIG. 2A, the inclined surfaces
11a each having an inclination angle .theta. are formed on the
engagement portions 11b in order to maintain the angle .theta.
between the optical portion 21 and the support portions 22 of the
intraocular lens 20.
[0046] The top member 12 to be inserted into the top surface
opening 11c of the base member 11 has the hollow nipping member 14
having a rectangular frame-like shape, and the above-mentioned push
member 13 disposed in the nipping member 14 to be movable in the
vertical direction. The bottom surface 14b of the nipping member 14
has the inclined surfaces 14a corresponding to the inclined
surfaces 11a of the engagement portions 11b of the base member 11.
Upper and lower depressions 14d and 14e are formed at a
predetermined interval on each of the inner surfaces 14c of the
opposite lateral walls such that the upper depressions 14d are
opposed to each other and the lower depression 14e are opposed to
each other.
[0047] The above-mentioned push member 13 is inserted into the
opening 14f of the nipping member 14 and is pressed downward in
order to move the intraocular lens 20 from the standby position to
the insertion position. The push member 13 has a head portion 13a
of a large diameter and a prism-shaped leg portion 13b. Protrusions
13c are formed on the peripheral surface thereof and in the
vicinity of the lower end thereof so as to be engaged selectively
with the upper depressions 14d or the lower depressions 14e of the
nipping member 14. Specifically, at the standby position, the
protrusions 13c of the push member 13 engage the depressions 14d,
and when the push member 13 is pressed, the protrusions 13c move
downward and come into engagement with the depressions 14e. A
concave surface 13d is formed on the bottom surface of the leg
portion 13b, and a ridge 13f for supporting the peripheral portion
of the intraocular lens 20 is formed on the concave surface
13d.
[0048] When the intraocular lens 20 is to be moved from the first
or standby position shown in FIG. 3A to the second or insertion
position shown in FIG. 3B, the head portion 13a of the push member
13 of the top member 12 is pressed down such that the intraocular
lens 20 whose peripheral portion is partially nipped by the base
member 11 and the top member 12 of the lens holding member 10 is
moved to a lens movement portion 39 of the attachment portion 35.
The lens movement portion 39 has a shape of a concavely-curved
groove. Thus, the peripheral portion of the intraocular lens 20
comes into engagement with the reverse surfaces of the opening
projection edges 39b provided at the opening of the curved concave
portion 39a. As a result of this movement, the vertical position of
the center of the lens 20 coincides with the center axis of the
push rod 33 substantially. When the push rod 33 is advanced, the
intraocular lens 20 is moved within the space 15 of the lens
movement portion 39 in a direction perpendicular to the page of
FIG. 3B, passed through the insertion tube 32 provided integrally
with the attachment portion 35, and is then pushed into the
eye.
[0049] Since upon pressing of the push member 13 the protrusions
13c come into engagement with the depressions 14e, the intraocular
lens 20 having been moved to the lens movement portion 39 is
prevented from reassuming its original shape, and reliable
positioning is effected.
[0050] The lens holding member 10 is preferably formed of
transparent or semi-transparent material, which allows an operator
to check whether the lens 20 has been moved to the lens movement
portion 39.
[0051] Further, it becomes possible to check whether the space 15
for allowing movement of the intraocular lens 20 is formed between
the lower surface of the top member 12 and the lens movement
portion 39 of the attachment portion 35. In other words, the push
member 13 of the top member 12 provides two functions; i.e., the
function for moving the lens 20 downward and the function for
forming the lens movement space 15 in cooperation with the
attachment portion 35.
[0052] As described above, the lens holding member 10 of the
embodiment--which consists of the base member 11 and the top member
12 including the nipping member 14 and the push member
13--functions as a portion of the mechanism of the insertion device
30 upon attachment thereto.
[0053] In the above described embodiment, the tubular main body 31
of the insertion device 30 and the lens holding member 10 are
assembled in order to complete the insertion device 30. However,
the base member 11 may be formed integrally with the attachment
portion 35 of the tubular main body 31. Further, the top member 12
may be formed integrally with the base member 11 such that the top
member 12 is connected to one end portion of the upper surface of
the base member 11 via a hinge.
[0054] Further, the present embodiment is characterized in that a
portion of deforming means for deforming the intraocular lens 20 to
a reduced size is formed integrally with the lens holding member
10.
[0055] That is, when the lens is moved to the lens movement portion
39 of the attachment portion 35, the lens is deformed to a reduced
size. This size reduction is achieved by three design features;
i.e., the lens movement portion 39 being formed into a form of a
curved groove, the lens 20 being moved while be pressed toward the
lens movement portion 39 by the top member 12, and the dimension J
of the lens movement portion 39 being smaller than the dimension K
of the lens 20.
[0056] FIG. 4 is a plan view showing a modified example of the
insertion tube 32 of the insertion device 30 used in the embodiment
of the present invention. In this modification, the insertion tube
32 is formed integrally with the attachment portion 35 of the
insertion device 30, such that a groove-shaped curved depression
39a serving as lens deforming means is formed on the side of the
base end 32b of the insertion tube 32. The intraocular lens 20
having being deformed to a slightly smaller size is deformed to a
further smaller size by means of the taper 32c which is formed on
the inner wall of the insertion tube 32 such that the diameter of
the through hole decreases toward the tip end of the insertion tube
32.
[0057] The space 15 has a shape and size such that movement of the
intraocular lens 20 within the chamber 15 is restricted. Further,
the shape of the space 15 is determined such that the optical
portion 21 of the intraocular lens 20 does not come into contact
with the inner surface of the base member 11 and the inner surface
of the top member 12, thereby preventing the optical
characteristics of the optical portion 21 from changing due to
force acting on the optical portion 21, during storage for a long
period of time.
[0058] Since such an intraocular-lens insertion system must be used
in a germ-free environment, during actual use of the insertion
system, an operator must use the system while wearing gloves, which
hinders fine operation. Therefore, the above-described attachment
method is preferable, because an operator can perform the operation
of moving the intraocular lens 20 from the first or standby
position to the second or insertion position by pressing the push
member 13 of the lens holding member 10 from above and inserting
the lens 20 from the insertion device 30 into the eye, while
holding the insertion device 30, which is larger and easier to hold
than the lens holding member 10.
[0059] In the above-described embodiment, the lens holding member
10 and the insertion tube 32 form deforming means for deforming the
intraocular lens 20. However, the present invention is not limited
thereto, and the configuration of the system may be modified to
assume various configurations; e.g., a configuration such that only
the lens holding member 10 is used to deform the intraocular lens
20 to a small size suitable for insertion into the eye, and the
thus-deformed lens 20 is passed through the insertion tube 32 and
inserted into the eye; and a configuration such that deforming
means is not provided on the lens holding member 10, but is
provided on the insertion tube 32.
[0060] In the specification, the term "center of the intraocular
lens 20" refers to the center in the thickness direction located on
the optical axis of the optical portion 21.
[0061] Obviously, numerous modifications and variations of the
present invention are possible in light of the above teachings. It
is therefore to be understood that within the scope of the appended
claims, the present invention may be practiced otherwise than as
specifically described herein.
* * * * *